////////////////////////////////////////////////////////////////////////////////
// Filename: bumpmap.ps
////////////////////////////////////////////////////////////////////////////////


/////////////
// GLOBALS //
/////////////
Texture2D shaderTextures[2];
SamplerState SampleType;

cbuffer LightBuffer
{
	float4 diffuseColor;
};


//////////////
// TYPEDEFS //
//////////////
struct PixelInputType
{
    float4 position : SV_POSITION;
    float2 tex : TEXCOORD0;
   	float3 normal : NORMAL;
	float3 tangent : TANGENT;
	float3 binormal : BINORMAL;
};


////////////////////////////////////////////////////////////////////////////////
// Pixel Shader
////////////////////////////////////////////////////////////////////////////////
float4 normalMaplShader(PixelInputType input) : SV_TARGET
{
	float4 textureColor;
    float4 bumpMap;
    float3 bumpNormal;
    float3 lightDir;
    float lightIntensity;
    float4 color;


    // Sample the texture pixel at this location.
    textureColor = shaderTextures[0].Sample(SampleType, input.tex);
	
    // Sample the pixel in the bump map.
    bumpMap = shaderTextures[1].Sample(SampleType, input.tex);

    // Expand the range of the normal value from (0, +1) to (-1, +1).
    bumpMap = (bumpMap * 2.0f) - 1.0f;
    
    // Calculate the normal from the data in the bump map.
	//increase x both y , normal effect will be to clear
    bumpNormal = (bumpMap.x * input.tangent  ) + (bumpMap.y * input.binormal) + (bumpMap.z * input.normal);
	
    // Normalize the resulting bump normal.
    bumpNormal = normalize(bumpNormal);

    // Invert the light direction for calculations.
    lightDir = -float3(0,0,1);

    // Calculate the amount of light on this pixel based on the bump map normal value.
    lightIntensity = saturate(dot(bumpNormal, lightDir));

    // Determine the final diffuse color based on the diffuse color and the amount of light intensity.
    color = saturate(diffuseColor * lightIntensity);

    // Combine the final bump light color with the texture color.
    color = color * textureColor;
	
    return color;
}
